Like many of my generation, I read about Thor Heyerdahl and his raft the Kon-Tiki as a child. The voyage in 1947 was a sensation, spawning books and a movie, which seemed to prove the possibility that the Polynesian islands were settled by sailors from South America drifting on ocean currents. It was a theory that has been discussed ever since Captain Cook landed in Hawaii in 1778 and found that the language of Tahiti was understood in Hawaii. That raised the question of where the Polynesians came from and how they interconnected. Prominent European historians and navigators believed the Pacific islands must have been settled from the east, possibly even from Europe, while a Maori scholar gathered and presented evidence for the idea that the islands were settled by travelers from Asia sailing by traditional navigation techniques.

But skeptics remained, the most famous—but by no means the only—was Thor Heyerdahl. Not only did he reject the voyaging tradition, but he rejected the West-to-East migration as well. Heyerdahl argued that the Pacific had been settled by accidental drift voyaging from the Americas. His argument was based largely on the wind and current patterns in the Pacific, which flow predominantly from East to West. Where the oral tradition posed Polynesians voyaging against the wind, Heyerdahl argued it was far more likely that American Indians drifted with the wind. He made his bias particularly clear by designing his Kon Tiki raft to be unsteerable.

There is no doubt that the voyage of the Kon Tiki was a great adventure: three months on the open sea on a raft, drifting at the mercy of the winds and currents. That they did eventually reach Polynesia proved that such drift voyaging was possible. But all other evidence pointed to Southeast Asian origins: oral tradition, archaeological data, linguistic structures and the trail of human-introduced plants. Today we have strong evidence that Polynesians actually reached the Americas, not vice-versa. Nonetheless, Heyerdahl remains famous. His notion of “drift voyaging” was taken up by Andrew Sharp, whose 1963 book discredited step-by-step the possible means by which Pacific Islanders might have navigated and fixed their position at sea.

Polynesian historians have maintained that traditional navigation led the way to Pacific exploration. In 1976, master traditional navigator Mau Piailug steered the Hawaiian canoe Hōkūleʻa (pictured) on a three-year voyage to all the Polynesian islands to prove how the ancient navigational techniques worked, and how sailors from Asia discovered and settled the islands. These techniques include intimate knowledge of the sun, stars, wind, weather, wildlife, and even the different types of ocean swells. Read how theories of ancient navigation and settlement have changed at Smithsonian. Also included is a documentary about Mau Piailug.